Fuel injection system



A ril 2, 1957 R. J. POWELL ETAL 2,787,257

FUEL INJECTION SYSTEM Filed Oct. 27, 1954 3 Sheets-Sheet l FIGJ.

IN V EN TORS ROBERT J. POWELL BY JAMES E.CHAMPION ATTORNEYS April 2, 1957 R. J. POWELL ETAL FUEL INJECTION SYSTEM 3 Sheets-Sheet 2 Filed Oct. 27, 1954 FIGJQ INVENTORS ROBERT J. POWELL y JAMES E.GHAMPION M1 1? ATTOR EYS April 2, 1957 R. .1. POWELL E'I 'AL 2,787,257

FUEL- INJECTION SYSTEM I Filed Oct. 27, 1954 3 Sheets-Sheet 3 FROM FUEL PUMP-+ e4 FIG.4. 3o

TO CLYLRNDER \62 INTAKE MANIFOLD CONNECTOR TUBES INVENTORS ROBERT J. POWELL BY JAMES E.CHAMPION ATTORNEYS FUEL ENJECTION SYSTEM Robert J. Powell and James E. Champion, Muskegon, Mich, assignors to Continental Motors Corporation, Detroit, Mich, a corporation of Virginia Application October 27, 1954, Serial No. 464,953

9 Claims. (Cl. 123-28) This invention relates to a fuel injection system and more particularly to such a system having a uni-flow fuel injector for direct injection of fuel from a collecting distributor chamber into the several intake manifold connector tubes leading from the manifold to the individual cylinder of a multi-cylinder internal combustion engine, and which is more particularly applicable to a multi-cylinder aircraft engine.

Several difliculties arise in aircraft engine operation which have been successfully met by a fuel injection system. Problems such as icing and fuel distribution to several cylinders are solved by having fuel injection into the air-fuel manifold. The instant invention represents a further improvement in fuel injection systems for aircraft engines of the type indicated by providing direct fuel injection into manifold connector tubes closely adjacent the entry port to the cylinders.

A centralized fuel distribution chamber is provided in the construction, having individually arranged communication lines leading to the cylinder manifold connectors. The fuel distribution chamber is formed as an integral part of the fuel injector.

It is therefore an object of the invention to provide a fuel injection system for a multi-cylinder internal combustion engine having a fuel injection construction with a distribution chamber leading to individual cylinder communication lines, which lines have direct entry to airfuel intake manifold connectors closely adjacent the in dividual cylinder intake valves, so that fuel is delivered in measured quantities for more efiicient engine performance.

For a more detailed understanding of the invention, reference may be made to the accompanying drawings illustrating a preferred embodiment of the invention in which like portions are referred to by like reference characters throughout the several views, and in which:

Fig. 1 is a side elevational view of a multi-cylinder internal combustion engine of the opposed cylinder type embodying the inventive construction,

Fig. 1a is a top view of the engine,

Fig. 2 is an enlarged vertical sectional view substantially central of the longitudinal axis of the fuel injector.

Fig. 3 is an enlarged vertical sectional view taken substantially on the line 3-3 of Fig. 2, and t Fig. 4 is an enlarged vertical sectional view taken substantially on the line 4-4 of Fig. 2.

As shown in the several views of the drawing, and more particularly in Fig. '1, the aircraft multi-cylinder internal combustion engine is provided with a cylinder block structure 12 having cylinders 14, an air throttle valve mechanism 15, an intake manifold 16 having lateral runners 18 with spaced manifold connector tubes 20 running directly to each of the cylinders 14. A fuel pump (not shown) of conventional characteristics is carried and driven by the engine, supplying a fuel injector 22 via a connecting conduit 24.

The engine manifold 16 is connectedwith a primary air intake suction pipe 26. Air is delivered to the intake tates Fatehtf) side 28 of pipe 26, and is passed through a control valve 15 to the manifold 16 where it is distributed to the various connector tubes or port runners 20 leading to the cylinders 14.

The fuel injector 22 is connected to thefuel pump by fuel supply conduit 24. The injector 22 comprises a housing 30 that is mountable directly upon the engine block structure 12, a fuel entry passage 32, a central longitudinal sleeve 34 and a pair of coaxial shafts 36 and 38, rotatably supported within sleeve 34. Shafts 36 and 38 abut each other, within sleeve .34, making a seal therebetween. Shaft 36 is provided with an undercut end portion 40, about which is disposed a coiled helical spring 42 urging shaft 36 against shaft 38. An end seal disc 44 against a snap ring 46 seated in housing 30 provides the seat for spring 42. The terminal end of shaft portion 40 is arranged to hold a lever hub 48 that rotates shaft 36 in accordance with the operating range of engine 10. Lever hub 48 is directly connected by lever connector 49 or other suitable means to a bell- 'crank lever 51, which operates the air. throttle valve 15 in riser 26. Lever 51 is movably responsive to air throttle means manually or otherwise controlled and actuated to vary the engine speed.

Shaft 38 is provided with a reduced portion 50 immediately adjacent the fuel entry passage 32. Portion 5f provides a fuel chamber 52 within sleeve 34. A communicating passage 54 leads from chamber '52 to the end of shaft 38 terminating in discharge port 55. Shaft 36 has an eccentric notched or cut-away end portion abutting shaft 38 which provides a rotatable eccentric cham ber 56 defined by sleeve 34, a wall 58 and an eccentric base 69 at the end of shaft 36. The outer end 50a ing chamber 64 about a portion of sleeve 34. A nozzle passage 66 in sleeve 34 provides communication between chamber 56 and chamber 64, said annular chamber 64 being constructed by enlarging a mid section of the bore in the housing 30 which supports the sleeve 34 so that the chamber 64 encircles the sleeve.

it may be observed that this construction is particularly applicable to a horizontally opposed cylinder engine, the injector 22 being mounted centrally on the top side of the crankcase substantially equidistant from the two banks of opposed engine cylinders, and therefore makes possible the locating of two banks of longitudinally spaced outlets 62 providing for uniform distribution of fuel to the engine cylinders.

An overflow valve structure 68 provides a means for controlling the taking of excess fuel from entry passage 32 and emitting it through a small jet opening 70, against a spring loaded relief valve 72 and out a fuel return line 74 to the fuel tank or the intake side 'of the fuel pump.

Fuel outlet ports 62 are provided with conduit lines 76 mounted in housing 30 at the outer ends of the ports, the lines leading directly to the individual cylinder manifold connector tubes 20, closely adjacent the cylinder intake valves.

In normal engine operation, the relation. of fuel port throughout the operating range. The fuel supply is'in-" creased by opening up the port 55 to its widest opening.

Patented Apr. 2, 1957 This occurs when the demand for fuel is at a peak, such as when the engine is warmed up prior to take-off, and When the aircraft is actually taking off.

The spring loaded relief valve 72 of valve structure prov des a means formaintaining the fuel in the injector under a desired minimum pressure throughout the system. The relief valve is adjusted to maintain a minimum pressure of about ten pounds, surplus fuel being discharged back through line 74.

To take care of increased engine speeds while tl throttle remains fixed, a pre-set jet 78, ahead of jet opening 70 and relief valve 72, is provided in valve structure 63. The increased amount of fuel being delivered due to increased engine speeds backs up in passage 32 ahead of jet 78, resulting in a corresponding increase in pressure and fuel flow through chamber 52, pas-sage 54, port 55, chamber 56, passage 66, chamber 64, and out of ports as and into conduits 76 leading to the individual cylinder manifold connector tubes 20. Thus, the fuel supply is slightly increased by the injector system pressure to meet the engine demand for fuel for operation at the increased speeds. A reduction in engine speed return-s the fuel pressure to normal.

Individual metering of fuel to the cylinders via the inector system of this invention provides for a more positive control of fuel-air mixtures at the point of cylinder entry.

It will be apparent to those skilled in the art to which the invention pertains that various changes and modificatrons may be made without departing from the spirit of the invention, or from the scope of the appended claims.

We claim:

1. A fuel injection system for direct injection of fuel into individual cylinder intake manifold connectors of an internal combustion engine, said engine having a primary induction conduit open to a source of air supply and connected with the engine intake manifold and provided with an air throttle valve adapted to vary engine speed, a fuel injection means operatively connected to said air throttle valve, said fuel injection means comprising a housing, regulatable fuel discharge means within said housing and having a fuel discharge port, means connected solely to said air throttle valve and operable only by said air throttle valve to vary the fuel discharge port opening directly with the opening of said air throttle valve, a fuel discharge distributing chamber in communication with said discharge port, individual cylinder fuel discharge passages In said housing communicating with said discharge chamher on the one end and with conduits connected to said intake manifold connectors on the other end, and means adapted to maintain a predetermined minimum fuel pressure in the fuel injector system.

2. A fuel injection system for direct injection of fuel into individual cylinder intake manifold connectors of an internal combustion engine, said engine having a primary induction conduit open to a source of air supply and connected With the engine intake manifold and provided with air throttle valve adapted to vary engine speed, a fuel pump driven by said engine and operable to deliver variable qualities of fuel in direct proportion to engine speed, a fuel injector means operatively connected to said air throttle valve, said fuel injector means comprising a houring and Within said housing a regul-atable fuel discharge means having a fuel discharge port, means connected solely to said air throttle valve and automatically operable only thereby to vary the fuel discharge port opening directly With the opening of said throttle valve, a fuel discharge distributing chamber in communication with said discharge port, individual cylinder fuel discharge passages in said housing communicating with said discharge chamher and with conduits connected to said intake manifold connectors, and means adapted to maintain a predetermined minimum fuel pressure in said fuel injector system whereby to effectively increase fuel flow through said fuel discharge port to enrich the fuel mixture delivered to said engine for increased engine speed at a fixed throttle setting.

- variable quantities of fuel in direct proportion to engine speed, a fuel injector means spaced apart from and opera tively connected to said air throttle valve, said fuel injection means comprising a housing and within said housing a regulatable fuel discharge port, means connected solely to said air throttle valve and automatically operable only thereby to vary the fuel discharge port opening directly with the opening of said air throttle valve, fuel discharge distributing chamber in comm nication with said discharge port, individual cylinder discharge passages in said housing leading from said distributing chamber to conduits connected to said intake manifold connectors, and other means automatically operable to effect an increase of fuel pressure at said fuel discharge port in response only to increased fuel pump delivery occasioned by increased engine speed While the air throttle valve and fuel discharge port area remain substantial-1y fixed, whereby to effectively increase fuel flow through said fuel discharge port to which the fuel mixture delivered to said engine for said increased engine speed with a fixed engine throttle, said other means comprising a fuel relief jet of fixed size.

4. The fuel injection system defined in claim 3, and in which said other means further comprises a pre-set fuel relief valve for maintaining a minimum fuel pressure in said fuel supply line for idling engine operation.

5. A fuel injection system for direct injection of fuel into individual cylinder intake manifold connector tubes of an internal combustion engine, said engine having a primary induction conduit open to a source of air supply and connected With the engine intake manifold and provided with an air throttle valve adapted to vary engine speed, a fuel pump driven by said engine and operable to deliver variable quantities of fuel in direct proportion to engine speed, a fuel injector means comprising a housing, and within said housing a single regulatable fuel discharge port operatively connected only to said air throttle valve to vary the fuel discharge port opening directly with the opening of said throttle valve, whereby to increase or decrease the area of said fuel discharge port as said air throttle valve is respectively opened or closed, a fuel discharge distributing chamber in communication with said discharge port, individual cylinder fuel discharge passages in said housing communicating with said discharge chamber and with conduits connected to said intake manifold connector tubes, means adapted to maintain a predetermined minimum fuel pressure in said fuel injector system whereby to effectively increase fuel flow through said fuel discharge port to enrich the fuel mixture delivered to said engine for increased engine speed with a fixed throttle setting, and manually operated means for varying the fuel discharge port area independently of said air throttle valve control.

6. The fuel injection system defined by claim 5, in which said fuel injector means further comprises a tubular member disposed in said housing transversely of said primary induction conduit and having a fuel discharge nozzle located generally medial of said tubular member, a pair of axially aligned shafts rotatably supported in said tubular member and having abutting end faces yieldingly urged together, one of said shafts connected with said air throttle valve and rotated therewith, said manually operated means connected to said other shaft for angular adjustment independently of the air throttle valve adjustment, said first shaft having an eccentric outer chamber in registry with said fuel discharge nozzle of said tubular member, said other shaft having a fuel passage terminating in said fuel discharge port in the end face abutting said first mentioned shaft and registering with said eccentric chamber, said first shaft operable to move said eccentric chamber, across the face of said fuel discharge port in said second shaft whereby to progressively open said port as said first shaft is rotated in opening the air throttle valve, said fuel discharge distributing chamber annularly surrounding said tubular member and in communication with said eccentric chamber via said discharge nozzle.

7. A fuel injection system for direct injection of fuel into individual cylinder intake manifold connectors of an internal combustion engine, said engine having a primary induction conduit open to a source of air supply and connected with the engine intake manifold and provided with an air throttle valve adapted to vary the engine speed, a fuel pump driven by said engine and operable to deliver variable quantities of fuel in direct proportion to engine speed, a fuel injector means spaced apart from and operatively connected to said air throttle valve, said fuel injector means comprising a tubular member disposed transversely of the primary induction conduit and having a fuel discharge nozzle facing upstream of said conduit located generally medial of said tubular member, a fuel discharge distributing chamber annularly surrounding said tubular member and in communication with said discharge nozzle, individual cylinder fuel discharge conduits leading from said distributing chamber into said intake manifold connectors, a pair of axially aligned shafts rotat-ably supported in said tubular member and having abutting end faces yieldingly urged together, one of said shafts connected with said air throttle valve and rotated therewith, means for angularly adjusting said other shaft independently of the air throttle valve adjustment, said first shaft having an eccentric outer chamber registering with said fuel discharge nozzle of said tubular member, said other shaft having a fuel passage terminating in a port in the end face abutting said first mentioned shaft and registering with said eccentric chamber, said first shaft operable to move said eccentric chamber across the face of said part in said second shaft whereby to progressively open said port as said first shaft is rotated on opening the air throttle valve, the fuel passage of said second shaft openly communicating with the delivery side of said fuel pump, and manually operated means for adjusting the relative angular positions of said first and second shafts for varying the proportions of the fuel and air mixture being supplied to said engine.

8. A fuel injection device for a horizontal opposed multicylinder internal combustion engine having an air throttle valve adapted to vary engine speed, said fuel injection device comprising an elongated housing mounted on the engine crankcase and having a longitudinal bore, a sleeve mounted in said bore, the midsection of said bore being enlarged to provide an annular chamber encircling said sleeve, and a fuel inlet port in said sleeve, and fuel metering means within said sleeve and operatively connected solely to said air throttle valve, said means operable in response to engine speed to supply measured amounts of fuel to the said fuel port, and separate fuel ducts connecting said annular chamber with individual engine cylinders, there being two banks of fuel ducts longitudinally spaced of said annular chamber, each bank of fuel ducts serving respectively a bank of engine cylinders.

9. A fuel injection means for multi-cylinder internal combustion engine having an air throttle valve adapted to vary engine speed, a crankcase and longitudinally opposed engine cylinders, one bank of cylinders extending laterally to one side of the crankcase and another bank of cylinders extending laterally to the other side of said crankcase, a looped air induction manifold for said engine and having separate port runners connecting said manifold with individual engine cylinders, an injector mounted directly on top of said crankcase substantially centrally thereof and substantially equidistant from said opposed banks of engine cylinders and comprising an elongated housing having a longitudinal bore, a sleeve fixed in said bore, the midsection of said bore being enlarged to provide an elongated annular chamber encircling said sleeve, a fuel inlet portion in said sleeve, fuel metering means within said sleeve and operatively connected solely to said air throttle valve, said means operable in response to engine speed to supply a variable supply of fuel to said fuel inlet port, said housing having oppositely extending fuel outlet passages openly connected with said annular chamber and horizontally spaced in said annular chamber, one outlet passage for each engine cylinder, and ducts connecting each of said outlet passages with the separate port runners, said ducts arranged in banks, each bank of ducts serving respectively a bank of engine cylinders.

References Cited in the file of this patent UNITED STATES PATENTS 2,136,959 Winfield Nov. 15, 1938 2,440,572 Brandenburg et a1 Apr. 27, 1948 2,633,187 Smith Mar. 31, 1953 

